Assaying-furnace.



4 Patented Apr. I, |902. A. C. CALKINS.

ASSAYING FURNACE.

(Application Bled Feb. 5. 1901.)

2 Sheets Sheet I.

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(No Model.)

W/ TNE SSE S A. C. CALKINS.

ASSAYING FURNACE .Application led Feb. 5, 1901.;

Patented Apr. l, |902.

2 Sheets--Sheetv 2.

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ALBERT OIIAMPLIN OAIJKINS, OF LOS ANGELES,'OALIFORNIA, ASSIGNOR TOFREDERICK W. BRAUN, OF LOS ANGELES, CALIFORNIA.

ASSAYlNG-FURNCE SPECIFICATION forming Dart Of Letters Faten No..696,548, dated April 1, 1902.

Application led February 5,1901. Serial No. 46,049. (No model.)

To all whom t may concern.-

Be it known that I, ALBERT CHAMPLIN OALKINS, residing at Los Angeles, inthe county of Los Angeles and State of California,

have made certain new and useful Improvements in Assaying-Furnaces, ofwhich the following is a specification.

My invention is an improvement in the class of assayers furnaces whichare adapted for ro use of gas or a volatizable hydrocarbon as a heatingmedium. It is more particularly a combined muiiie and melting-furnace,and anV improvement upon, or in the same line as, those covered by thepatents of J. J. Louer- :5 gan and A. C. Oalkins, No. 608,883, and G.NV. Martin and A. J. Petter, No. 635,586.

The features of improvement and novelty are as hereinafter described,and shown in accompanying drawings, in whichzo Figure l is a perspectiveview of my improved furnace, part being broken away to show interiorconstruction. Fig. 2 is a central vertical transverse section of thefurnace. Fig. 8 is an elevation of one end of the central portion of thefurnace. Fig. i is an end view of one longitudinal half and a Verticalsection of the corresponding half of the furnace. Fig. 5 shows amodified construction. The furnace has two main divisions-to wit, 3o thecentral portion A, containing the muffie l, and two sidecrucible-chambersB B, which are similar in form, construction,arrangement, and operation. The sides of the furnace are incased bysheet or cast metal,which l 3 5 extends below the fire-brick and isprovided with Ventilating-openings. Themuiiie is arranged. transverselyof the central part A and traverses a combustion-chamber 2, having aside opening 3 for introduction of a suitable 4o gas or hydrocarbonburner. (Not shown.) From such combustionchamber 2 a iiue et (see Fig.2) leads to the bonnet O, which is constructed of sheet metal and setand held detachably upon the top of part A. The front end of the muiiiel is entirely open, and the rear or inner end has an opening 5, whichcommunicates with a passage 6, extending through the rear end wall ofthe furnace portion A. The said passage 6 is guarded by a 5o pivoteddrop cover or valve 7 and serves as an inspection-opening and foradmission of air as may required for the best results in oxidation andreduction.

From the front end of the muiile l a passage 8 (see Figs. land 2) leadsupward, it be- 55 ing formed in the end of the arch of thecombustion-chamber 2, and, like the main flue 4., it leads direct intothe bonnet C. This passage 8 may be closed by the plug or block 9, whichis adapted to fit and slide in a hori- 6o zontal passage formed in thefront wall of part A, in alinement with the muifle l. The said plug 8 isadapted to slide in a hood 9, having a bottom shelf or bracket whereinthe plug rests, as shown. Thus when pushed in against the end of themu'lile 1, as shown by dotted lines, Fig. 2, it closes or shuts off thepassage 8, and when drawn out, as shown in full lines, the said passage8 is left free or open. 7o

It will be understood that the air for oxidining the charge in themuffle is admitted through the passage 6 in the back of the furnace Aand that a draft through the front passage 8 is induced by the draft inthe main 75 iiue A. Thus the draft through the mufiie l may be perfectlyregulated and any desired amount of oxygen may be supplied, as theconditions of the cupeling operation require.

As shown in Figs. 2 and A, the central com- 8o bustion-chamber 2 haswide lateral passages l0, that lead into the side crucible-chambers B.Each of the latter has a base which may be formed wholly or in part ofiireclay ll, whereon crucibles or melting-pots are set, as shown bydotted lines, Fig. 4. A bottom slide 13 provides for convenient removalof the clay. In use the flame and heated gases pass from the central andmain chamber 2 through passages l0 into the side 9o chambers B, whichserve practically as combustion-chambers, wherein the crucibles areexposed to a practically uniform heat.

It will be noted that the bottom of the combustion-chamber 2 is iiushwith that of the 95 side or Crucible chambers B, as shown in Fig.

4.. This allows crucibles to be placed in the space beneath the arch, aswell as in chambers B, proper. The latter may be provided roo withcovers 12, arranged horizontal, as shown in Fig. l; but my preferredconstruction and arrangement are shown in Fig. 5, wherein the centralarch of the furnace is shown extended laterally over theCrucible-chambers B, and the latter are provided with a cover or door12, consisting ot' a block fitted into a longitudinal opening andsupported by the converging sides or angles of such opening. Through thelatter access is had to the crucible-chamber for convenient insertion orremoval of crucibles. It Will be seen that by this extension of the toparch over the crucible-chambers B and the extension of the Iioor of thelatter flush with that of the combustion-chamber 2 I am enabled tolessen the Width of the furnace as compared with the form shown in Fig.it Without decreasing its capacity for holding crucibles.

It is apparent that one of the chambers B may be used for cleanassay-Work while the other is being used for melting bullion.

What I claim isl. The improved assaying-furnace comprising acombustion-chamber having a main top liue, a mufde arranged horizontallyin said chamber and having its front end open, and its rear end providedwith an air-inlet and a device for regulating admission of air thereto,means for temporarily closing the front end of the muffle, and asupplemental flue or passage leading up from such end of the mutle,substantially as shown and described.

2. The improved assayin g-fu rn ace comprising a combustion-chamberhaving a main top iue, a muftle having its front end open, asupplemental iue or passage leading up from such end of the mufe, and aremovable plug adapted for closing both the muflie and said passage,substantially as shown and described.

The improved assaying-furnace, comprising a combustion-chamber having amain escape-flue and a bonnet therefor, a mule which traverses the saidchamber and is open at each end, passages in the side Walls of thefurnace which communicate with the muftle, a passage leading upward fromone end of the muffle and connecting with the main flue, a plug forclosing the passage and the adjacent end of the muflle, and a valve forclosing the opposite end of the muflle, substantially as shown anddescribed.

4. The improved assaying-furnace comprising a centralcombustion-chamber, having a fire-opening, a muil-le which traverses thechamber above such opening, Crucible-chambers located on each side ofthe main chamber, and lateral passages connecting the three chambers,the latter being provided with removable covers, substantially as shownand described.

ALBERT CHAMPLIN CALKINS.

Vitnesses:

SIDNEY J. PARSONS, TREVITT WV. OKEY.

